Exoplanets Archives

April 24, 2023April 24, 2023 by Carolyn Collins Petersen

If a Star Has Less Metals, it Might Have a Better Chance to Spark Life

An illustration of the variations among the more than 5,000 known exoplanets discovered since the 1990s. Could their stars' metallicity play a role in making them habitable to life? Credit: NASA/JPL-Caltech

In the hunt for habitable worlds around other stars, planetary atmospheres provide fertile places to look. But, as a group of scientists at the Max-Planck Institute for Solar System Studies in Germany found, maybe astronomers should focus on a star’s metallicity, too. That’s because there seems to be a direct link between their metallicity, how much UV radiation they give off, and the atmospheres of rocky planets orbiting them. It turns out that metal-poor stars provide better conditions for life on their planets than metal-rich ones do.

April 17, 2023April 17, 2023 by Evan Gough

Astronomers Find a Planet Using Gaia Data

Artist view of a Jupiter-like exoplanet. Credit: NASA/Goddard Space Flight Center/S. Wiessinger

The ESA’s Gaia mission is our most accurate star-measuring spacecraft. It’s busy mapping the positions and radial velocities of one billion stars in the Milky Way. The mission’s goal is to create a representative map of the galaxy’s stellar population with unprecedented accuracy. The mission has released 3 sets of data since its inception, leading to many discoveries.

Now a team of astronomers has found an exoplanet with help from Gaia, an unintended result of the ambitious mission.

April 9, 2023April 7, 2023 by Paul M. Sutter

Astronomers Find Out What Happens to Rocky Planets That Wander too Close to Their Stars

This artist's illustration shows the fiery exoplanet WASP-76b. Previous study shows the planet rains iron it's so hot. Now astronomers have detected barium in its atmosphere. Image Credit: ESO/M. Kornmesser

The massive Kepler survey found a treasure trove of exoplanets. But in all that wealth they found three anomalies: what appeared to be rings of dust surrounding stars where planets should be. They were rocky planets in the process of being obliterated. And a team of astronomers that found a way to use these gory sites to understand some of the most mysterious and hard to detect planets in the universe.

April 6, 2023April 6, 2023 by Carolyn Collins Petersen

Do Repeating Radio Signals Indicate an Exoplanet with a Magnetosphere?

An artist's conceptual rendering of interactions between a prospective exoplanet and its star. Plasma emitted from the star is deflected by the exoplanet's magnetic field (and magnetosphere) then interacts with the star's magnetic field, resulting in an aurora on the star and the emission of radio waves. Credit: National Science Foundation/Alice Kitterman — An artist's conceptual rendering of interactions between a prospective exoplanet and its star. Plasma emitted from the star is deflected by the exoplanet's magnetic field then interacts with the star's magnetic field, resulting in an aurora on the star and the emission of radio waves. Credit: National Science Foundation/Alice Kitterman

There’s an interesting problem in exoplanet studies: how to tell if a planet has a magnetosphere. It’s not like we can visibly see it unless we find a different way of looking. A pair of scientists may have found one. They used radio telescopes to track emissions given off by magnetic star-planet interactions. These happen when a planet with a magnetic field plows through star stuff caught its star’s magnetic field.

March 27, 2023March 27, 2023 by Nancy Atkinson

Finally, JWST's Data on the First TRAPPIST-1 Planet. Survey Says? It Sucks

This illustration shows what the hot rocky exoplanet TRAPPIST-1 b could look like. A new method can help determine what rocky exoplanets might have large reservoirs of subsurface water. Credits: NASA, ESA, CSA, J. Olmsted (STScI)

With the James Webb Space Telescope’s ability to detect and study the atmospheres of distant planets orbiting other stars, exoplanet enthusiasts have been anticipating JWST’s first data on some of the worlds in the famous TRAPPIST-1 system. This is the system where seven Earth-sized worlds are orbiting a red dwarf star, with several in the habitable zone.

Today, a new study was released on the innermost planet in the system, TRAPPIST-1 b. The authors of the study were quite frank: this world very likely has no atmosphere at all. Additionally, the conditions there for possible life as we know it only get worse from there.

March 23, 2023March 23, 2023 by Evan Gough

The Discovery of a Hot Neptune that Shouldn’t Exist

exoplanet hot jupiter transiting its star — This artist’s impression shows an ultra-hot exoplanet as it is about to transit in front of its host star. Credit: ESO

1800 light-years away, an unlikely survivor orbits an aged star. This rare planet is called a hot Neptune, and it’s one of only a small handful of hot Neptunes astronomers have found. Hot Neptunes are so close to their stars that the overpowering stellar radiation should’ve stripped away their atmospheres, leaving only a planetary core behind.

But this planet held onto its atmosphere somehow.

March 7, 2023March 7, 2023 by Evan Gough

TESS Shows That Even Small Stars Can Host Giant Planets

Massive planets can form around low-mass stars, but they're rare. Image Credit: NASA

Can low-mass stars play host to giant, Jupiter-sized planets? Theories of planet formation suggest that it’s highly unlikely. But a team of scientists in the UK found that it’s possible, though rare.

March 6, 2023March 7, 2023 by Paul M. Sutter

Stars Can Eat Their Planets…and Spit Them Back Out Again

As tragic as it is, engulfment of a planetary object by its stellar parent is a common scenario throughout the universe. But it doesn’t have to end in doom. A team of astrophysicists have used computer simulations to discover that planets can not only survive when their star eats them, but they can also drive its future evolution.

February 27, 2023February 27, 2023 by Evan Gough

Venus is Like an Exoplanet that’s Right Next Door

Venus' thick clouds mean that only radar imaging can reveal surface details. Image Credit: NASA/JPL-Caltech

We’re lucky to have a neighbour like Venus, even though it’s totally inhospitable, wildly different from the other rocky planets, and difficult to study. Its thick atmosphere obscures its surface, and only powerful radar can penetrate it. Its extreme atmospheric pressure and high temperatures are barriers to landers or rovers.

It’s like having a mysterious exoplanet next door.

February 26, 2023February 26, 2023 by Laurence Tognetti

The Planet That Shouldn’t Exist

Artist illustration of TOI-5205b orbiting its parent star. (Artwork Credit: Katherine Cain/Carnegie Institution for Science)

As of this writing, almost 5300 exoplanets spanning approximately 4000 planetary systems have been confirmed to exist in our universe. With each new exoplanet discovery, scientists continue to learn more about planetary formation and evolution that has already shaken our understanding of this process down to its very core. One such example is “Hot Jupiters”, which are Jupiter-sized exoplanets, or larger, that orbit closer to their parents stars than Mercury does to our own. This is in stark contrast to our own Solar System, which has rocky planets closer towards our Sun and the gas giant planets much farther out.